115913692521 has 135 divisors (see below), whose sum is σ = 201987797319. Its totient is φ = 66185618400.

The previous prime is 115913692513. The next prime is 115913692529. The reversal of 115913692521 is 125296319511.

The square root of 115913692521 is 340461.

It is a perfect power (a square), and thus also a powerful number.

115913692521 is a `hidden beast` number, since 1 + 1 + 5 + 9 + 1 + 36 + 92 + 521 = 666.

It is an interprime number because it is at equal distance from previous prime (115913692513) and next prime (115913692529).

It can be written as a sum of positive squares in only one way, i.e., 1277276121 + 114636416400 = 35739^2 + 338580^2 .

It is not a de Polignac number, because 115913692521 - 2³ = 115913692513 is a prime.

It is a super-2 number, since 2×115913692521² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (115913692529) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 640407051 + ... + 640407231.

Almost surely, 2^115913692521 is an apocalyptic number.

115913692521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

115913692521 is the 340461-st square number.

115913692521 is the 170231-st centered octagonal number.

It is an amenable number.

115913692521 is a deficient number, since it is larger than the sum of its proper divisors (86074104798).

115913692521 is an equidigital number, since it uses as much as digits as its factorization.

115913692521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434 (or 214 counting only the distinct ones).

The product of its digits is 145800, while the sum is 45.

The spelling of 115913692521 in words is "one hundred fifteen billion, nine hundred thirteen million, six hundred ninety-two thousand, five hundred twenty-one".